The present invention relates to a double-side automatic feeding apparatus for document, especially to a double-side automatic feeding apparatus with an E-shaped document traveling path and movable printing/scanning unit.
The computer printer is used to print out document such as text or picture from computer. The computer printer is generally connected to the parallel printer port of the computer and commanded by the computer for printing document.
The printers can be generally classified into dot-matrix printer; inkjet printer and laser printer. Among those, the dot-matrix printer has problem of poor quality and noise and become eclipsing. The inkjet printer prints document on paper by spraying ink thereon through a nozzle and is popular for personal usage. The laser printer has advantages of high quality and high speed. However, the laser printer has higher price and generally used by business.
Moreover, the scanners become popular peripherals for computer users as multimedia and web page design are gradually prevailing. The scanner generally senses a reflected light from a document of interest and converts the sensed light signal to a digital image signal for representing the document. The digital image signal can be processed with optical character recognition software to convert the digital image signal into textual file if the original document contains textual information.
However, the existing printer or scanner can only print/scan one side of a paper at each operation. For double-side printing, the paper should be taken out and turned over; this is inconvenient.
To scan double-sided document, scanner for double-sided image has been developed. FIG. 1 shows a prior art scanner for double-sided image, which comprises a paper feeder 10a, a paper outlet 11a at same side as the paper feeder 10a, a scanning region 12a having a document traveling path 13a bridging the paper feeder 10a and the paper outlet 11a, a transparent window 14a and a direction-controlling wheel 15a opposite to the transparent window 14a, a rotary means 16a having an entrance path and an exit path connected to scanning region 12a. The entrance path is used to guide a document with one scanned side from the scanning region 12a, the exit path flipping the document and sending the flipped document to the scanning region 12a such that an unscanned side of the document can be processed in the scanning region 12a. A sensor 17a is placed at the exit of the rotary means 16a and sends a detection signal to the direction-controlling wheel 15a when sensing the appearance of the document and the direction-controlling wheel 15a will be commanded to rotate at opposite direction. An image sensor 18a is arranged at an outer side of the transparent window 14a. When the document is fed through the paper feeder 10a and passes to the transparent window 14a, the image sensor 18a senses an image at a first side of the document. When the document is flipped by the rotary means 16a and then again passes to the transparent window 14a, the image sensor 18a senses an image at a second side of the document.
However, in above-mentioned double-sided image scanner, the document should be returned to the paper outlet 11a after a long trip with flip operation. Therefore, the propagation distance of the document is long and the scanning time is increased.
It is an object of the present invention to provide a double-side automatic feeding apparatus, wherein the document can be scanned on both sides thereof without cumbersome reverse movement.
It is another object of the present invention to provide a double-side automatic feeding apparatus with E-shaped document traveling path and movable printing/scanning unit.
To achieve above object, the present invention provides a double-side automatic feeding apparatus comprising a paper feeder, a first paper holder, a second paper holder, a document traveling path and a paper flipping unit. The paper feeder, the first paper holder and the second paper holder are arranged apart in longitudinal direction. The document traveling path is of E shape and connected to the paper feeder, the first paper holder and the second paper holder. The document traveling path is provided with a plurality of rollers to move a document from the paper feeder to one of the first paper holder and the second paper holder. The paper flipping unit is arranged in the document traveling path and can be trigger to flip the document during the document traveling path. By the double-side automatic feeding apparatus, a document can be selectively printed or scanned on single- or double-side thereof at user""s disposal.